The present invention relates to forage boxes and in particular to an improved mechanism for controlling a chain drive used to remove materials from the forage box.
Forage is generally plant material such as plant leaves and stems that may be eaten by grazing livestock but, as used herein, may also include other fodder material including grains and the like.
Forage is often transported to cattle or other animals through the use of a forage box supported on a trailer or truck for ready transport. The forage box may receive forage, for example, directly from a tractor-mounted shredder during a harvesting process, traveling next to the tractor during that harvesting. The forage boxes may then be transported to a location removed from the harvesting site where the forage will be stored or dispensed to the animals.
Typically forage boxes provide for a mechanism for ejecting forage from the forage box after the forage box has been filled. This mechanism is often in the form of an apron conveyor consisting of chains that pass along the floor of the forage box in a loop between separated and horizontally disposed front and rear driveshaft at the front and rear of the forage box floor. Rotation of the shafts causes the chains and crossbars on the chains to pull the forage along the floor and ejected the forage out of the box.
Versatile forage boxes may remove the forage from the rear of the box, typically to dispense the forage on the ground or in a ground-level container, or from the front of the box. Operating the forage box to remove forage from the front of the forage box offers finer control in the dispensing of the forage typically through a set of augers or similar feeder rollers which may meter the release of forage, for example, to be deposited on a cross conveyor, for example, for bagging or other operations.
During the front and rear unloading operations, the conveyor chains operate in opposite directions as driven by separate front and rear drive mechanisms associated with the front and rear driveshafts. These different drive mechanisms allow the upper length of the chain to always be operated in a pull, rather than push, fashion avoiding the need for complex and precise chain tensioning mechanisms.
It is critical that both of the front and rear drive mechanisms not be engaged at the same time such as could cause catastrophic failure of the equipment. Exclusive operation of only one of the front and rear drive mechanisms at a time is ensured through the use of a drive plate forming an essential mechanical coupling between each drive mechanism and its respective driveshaft. A single drive plate is provided that must be physically removed from the rear driveshaft to be placed on the front driveshaft in order to drive the front driveshaft, and physically removed from the front driveshaft to be placed on the rear driveshaft in order to drive the rear driveshaft. In this way, both driveshafts cannot be activated at the same time.